Merge tag 'smp-core-2020-03-30' of git://git.kernel.org/pub/scm/linux/kernel/git...

[linux-2.6-microblaze.git] / kernel / seccomp.c

diff --git a/kernel/seccomp.c b/kernel/seccomp.c
index b6ea3dc..ec5c606 100644 (file)
--- a/kernel/seccomp.c
+++ b/kernel/seccomp.c
@@ -528,8 +528,12 @@ static long seccomp_attach_filter(unsigned int flags,
                int ret;
 
                ret = seccomp_can_sync_threads();
-               if (ret)
-                       return ret;
+               if (ret) {
+                       if (flags & SECCOMP_FILTER_FLAG_TSYNC_ESRCH)
+                               return -ESRCH;
+                       else
+                               return ret;
+               }
        }
 
        /* Set log flag, if present. */
@@ -1221,6 +1225,7 @@ static const struct file_operations seccomp_notify_ops = {
        .poll = seccomp_notify_poll,
        .release = seccomp_notify_release,
        .unlocked_ioctl = seccomp_notify_ioctl,
+       .compat_ioctl = seccomp_notify_ioctl,
 };
 
 static struct file *init_listener(struct seccomp_filter *filter)
@@ -1288,10 +1293,12 @@ static long seccomp_set_mode_filter(unsigned int flags,
         * In the successful case, NEW_LISTENER returns the new listener fd.
         * But in the failure case, TSYNC returns the thread that died. If you
         * combine these two flags, there's no way to tell whether something
-        * succeeded or failed. So, let's disallow this combination.
+        * succeeded or failed. So, let's disallow this combination if the user
+        * has not explicitly requested no errors from TSYNC.
         */
        if ((flags & SECCOMP_FILTER_FLAG_TSYNC) &&
-           (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER))
+           (flags & SECCOMP_FILTER_FLAG_NEW_LISTENER) &&
+           ((flags & SECCOMP_FILTER_FLAG_TSYNC_ESRCH) == 0))
                return -EINVAL;
 
        /* Prepare the new filter before holding any locks. */